GENEALOGY-DNA-L Archives

Archiver > GENEALOGY-DNA > 2008-11 > 1228085219


From: "Michael Walsh" <>
Subject: Re: [DNA] TRMCA for R1b1
Date: Sun, 30 Nov 2008 16:46:59 -0600


My responses are in brackets [[ ]].

>Vincent Vizachero wrote:
> > 1) the variance of STR haplotypes within the major western European
> > clades is very low: consistent with the new theory but not with the
> > old.
Dienekes Pontikos wrote:
> That may be relevant to the arrival in Western Europe but not to
> Europe in general. And, it's not really relevant even for that, since
> the TMRCA of present-day R-M269 haplotypes could be either younger or
> older than the date of arrival of R-M269 in Europe; there is no a
> priori reason why the two should coincide.
My response: [[ The relevance of Western Europe is essential to
determining if the Iberan refugium theory for R-M269 holds true.
Remember that the confidence ranges for R1 (R-M269's ancestor) do not
precede the Last Glacial Maximum (LGM - last greatest expansion of the
Last Ice Age.) This makes the R1b in Iberia refugium "old theory"
nearly impossible. Your alternative hypothesis in this case is not
very credible..... that R-M269 was present in Europe pre-LGM but then
all died out but one thin lineage, while multiple diverse lineages
lived till the present day in SW/Central Asia, even though they are
more sparse (less frequent) today than in Western Europe.]]

>Vincent Vizachero wrote:
> > 2) the variance of STR haplotypes is higher in southeastern Europe
> > and southwestern Asia than in western Europe: consistent with the
> > new theory but not with the old.
Dienekes Pontikos wrote:
> The elevated variance may be due to multiple sources rather than
> antiquity. Certainly in the Balkans some R-M269 may have come from
> West Asia while other R-M269 may have come from Italy. Similarly,
> R-M269 in Turkey may be indigenous, or from the Balkans, or from
> Central Asia.
My response: [[ Even the "multiple sources" is indicative of
something, proximity to the source, which ultimately indicates
antiquity or relative age.]]

>Vincent Vizachero wrote:
> > 3) the oldest forms of R1b1b2 (those formerly called ht35 but which
> > now have SNP-based labels) are found progressively more frequently in
> > southeastern Europe and southwestern Asia than in western Europe:
> > consistent with the new theory but not with the old.
Dienekes Pontikos wrote:
> That may indicate the direction of the spread but not its age.
My response: [[ Direction indicates source, which implies relative age. ]]

>Vincent Vizachero wrote:
> > 4) the rate of SNP accumulation (i.e. the Karafet et al. method) puts
> > the TMRCA for R1 overall at 18.5 kya. The TMRCA for R1b1b2 must, by
> > definition, be younger than that - and according to STR variance, MUCH
> > younger: consistent with the new theory but not with the old.
Dienekes Pontikos wrote:
> The age of R1 is 12,500-25,700 according to Karafet et al. and this
> depends on an unfounded assumption that the age of CT is 70k. This
> assumption is not an independent SNP-based estimate, but is based on
> the 2002 paper by Hammer and Zegura.
> So, the evidence is quite consistent with a pre-Neolithic arrival of
> R-M269. There is certainly no convincing evidence that R-M269 arrived
> in Europe from 8kya onwards.
My response: [[ The age of CT at 70K is based on matching archeology
and genetics in Africa. If this is untrue, no other conversations
downstream (about later times) are relevant so we are all wasting our
time reading blogs or forums on anything downstream. This (CT at 70K)
is an unstated assumption in most arguments, but worthwhile or there
is no reason to hypothesize, period. In terms of your thought that
there is no "convincing evidence" that R-M269 arrived in Europe in the
Mesolith or later, "convincing" is your personal subjective standard.
There is no "convincing evidence" that R-M269 was in Europe during the
Paleothic pre-LGM timeframe. The question of logic is not whether one
meets your or my criterion for "convincing" but rather, what
alternative hypothesis is most probable. I was weaned on the R-M269
is Paleothic "old theory", but logic has convinced me this is not most
probable.]]

This thread: